Leaning over the Waverley’s varnished wooden handrail, the actor Timothy West watches a mooring rope splash into the sea and a steam capstan haul it on to the deck. With his wife Prunella Scales and 700 other passengers, he is spending a day on the world’s last sea-going paddle steamer.

Loosed from its ties to land, the ship takes on a life of its own. A mound of foamy water surges from the paddle-box, accompanied by a blast on the ship’s steam whistle, as we set off for a cruise on the Firth of Clyde in Scotland, where the Waverley was launched in 1946. The sound and rhythm of paddles threshing the sea picks up momentum as we pull away from Largs pier. Within a couple of minutes the ship is breezing along at a steady 14 knots, surrounded by a panorama of mountain, island and open horizon.

West, known for his versatile range of roles on stage and screen, is a lifelong devotee of paddle steamers. He and Scales, who played Sybil Fawlty in the BBC comedy series Fawlty Towers, visit Scotland every summer to sail on the Waverley. They chartered the ship in 2003 for their 40th wedding anniversary party on the Thames, where it operates a short season in September.

“If you’re my age, you have a particular idea of what a ship should look like,” says West, 77, his voice and appearance redolent of a sturdy old sea captain. “It is a thing of beauty with proper funnels, not like the ships of today, which resemble blocks of housing. Most people regard ships as a convenience, but a day’s excursion on a paddle steamer is more than that. You see the land from a different point of view, you watch the wildlife. It’s extremely relaxing, and there’s a companionship about being stuck with the same people for eight hours, that you don’t find in any other situation.”

Our day on the Waverley offers ample evidence. A constant swirl of seagulls accompanies the ship. Seals are espied off the island of Cumbrae. The sun may be struggling to come out, but as we head down Kilbrannan Sound towards Campbeltown, our destination on the Kintyre peninsula, everyone seems to be either lounging on deck or gazing at the ship’s gleaming wake. At one point Scottish dance band music pipes up on the public address system, and three couples spontaneously try out their steps, to the delight of other passengers.

Passengers on the promenade deck: "You see the land from a different point of view"

West expresses dismay that our island nation shows scant interest in its maritime heritage. The son of an actor who was “crazy” about paddle steamers, he spent childhood holidays on the Bristol Channel and the south coast, where his father’s professional engagements had a curious habit of coinciding with his private enthusiasms.

“I remember standing with him on Hotwells landing stage in Bristol on Easter Monday 1946, when the paddle steamer Ravenswood gave her first peacetime excursion after the war,” he says. “We watched this wonderful thing in salmon pink paint and shining brass coming towards us under the Clifton suspension bridge. Everyone cheered. Wartime grey had disappeared. Colour, hope and happiness had returned.”

While West and I have been nattering beneath the Waverley’s tall funnels, Scales has slipped below decks to sit in a cosy bar. Setting aside the embroidery she has brought to while away the time, she explains that she too has childhood associations with the sea: during the second world war she was evacuated to the Devon coast, where she was taught the rigging of sailing ships by a convalescent sailor.

West and Scales are active supporters of the Paddle Steamer Preservation Society, which bought the Waverley from her state-owned operator for £1 in 1973. By that time, the fleets of pleasure steamers that had been such a feature of Britain’s coasts since Victorian times had all but disappeared. Faced with mounting regulatory hurdles and a dearth of suitably skilled manpower, the Waverley has struggled to keep going in recent years.

No automated controls in sight

Unlike most steam relics, says West, “the Waverley is a practical entity, a working museum model. It’s similar to steam locomotives – there’s a great feeling of power, this enormous weight being driven by something as extraordinary and old-fashioned as steam. You’re moving on a relic of the Industrial Revolution, the legacy of Newcomen and Brunel. I’m potty about Victorian engineering!”

Watching the ship’s magnificent engines at work, it is hard not to share his enthusiasm. On our way back to the promenade deck, we absorb their Heath Robinson concoction of mechanical cranks, noises and smells, there for all to admire. A polished brass telegraph rings, signalling an order from the bridge. The engineer pulls his levers – no automated controls here – and the three giant rotating pistons which drive the paddle-shaft slow down as we approach Campbeltown pier.

Along with about half the ship’s complement, West and Scales opt to spend time ashore while the Waverley takes a short cruise to the Mull of Kintyre. Not long after though, the gangways are pulled away for the return journey to Largs. West observes that, while his generation looks on a paddle steamer as an object of nostalgia, “younger people seem to enjoy the Waverley for other reasons, not just the fresh air but the feeling of arriving as a traveller, which you don’t get in a car.”

With a following wind and plenty of late afternoon sun, it seems no time before we are back alongside Largs pier. As the ropes are thrown ashore and the steam capstan returns to life, West marvels at the “extraordinary energy” that has gone into preserving narrow-gauge steam railways around the UK and bemoans that “our paddle-steamer fleet hasn’t been treated in the same way. Most ships have a natural life of about 30 years. They’re a more complex prospect. We’re lucky we still have the Waverley.”

The Waverley operates on the Thames from September 29 to October 14; www.waverleyexcursions.co.uk/thames.htm. Timothy West stars in ‘The Handyman’, by Ronald Harwood, at Cheltenham’s Everyman Theatre from Monday and touring.

‘Pleasures of the Firth: Two Hundred Years of the Clyde Steamers’ by Andrew Clark will be published by Stenlake in October